Recent years have witnessed an explosion of mobile data traffic due to proliferation of smart terminals (e.g., smart phones and tablet personal computers) and increasing use of mobile applications. It is predicted that global mobile data traffic will increase eightfold between 2015 and 2020. Wireless operators are investing heavily in infrastructure, including increasingly denser deployment of access points (APs) to improve cellular coverage and capacity for homes and businesses in urban, suburban, as well as rural areas.